1. Technical Field
The present invention relates in general to object identification and in particular to identification of objects distributed among a plurality of data processing systems and/or data processing system networks. Still more particularly, the present invention relates to unique identification of objects within a data processing system which forms a portion of a database of objects distributed among a plurality of data processing systems and/or data processing system networks without requiring the host data processing system to be connected to any other data processing system at the time the object identifier is assigned.
2. Description of the Related Art
Objects frequently require an identification which is unique, as in cases where the object forms a portion of a database of objects. Various solutions exist to provide unique object identifiers within a single data processing system whenever an object is added to the data processing system. A common solution is to utilize a central registry to assign a numerical identifier to a new object from a sequential set of numbers under the control management of the central registry. When an object identifier for a new object is requested, the central registry increments the last number assigned to an object and provides the result as a unique number satisfying the request.
In certain situations, an object must have an identification which is unique within a plurality or network of data processing systems, as in cases where the object forms a portion of a database of objects distributed among the plurality of data processing systems. The object identifier must be unique when the corresponding object is added to one of the data processing systems within the network. In such circumstances, the solution of a central registry requires that the data processing system to which the object is being added be connected to the central registry at the time the object is added. This requirement may be burdensome, particularly where the objects are distributed among data processing systems communicating over the Internet, where limited bandwidth may preclude connection to the central registry at the time an object must be added.
One alternative is to assign different ranges of object identifiers to different data processing systems in a network or system of networks. When a new object is added to a particular data processing system, the object identifier is selected from the range of identifiers assigned to that data processing system. This method is limited, however, due to the possibilities of exhausting the numbers within a range and exhausting the number of ranges. Sufficient ranges need to be reserved for future additions of data processing systems.
It would be desirable, therefore, to provide a method and apparatus for uniquely identifying an object within a data processing system forming a network which forms, in turn, a system of networks. It would further be desirable for the uniqueness of the object identifier to be guaranteed even if the host data processing system is not connected to any other data processing system at the time the object is added.
It is therefore one object of the present invention to provide a method and apparatus for object identification.
It is another object of the present invention to provide a method and apparatus for identification of objects distributed among a plurality of data processing systems and/or data processing system networks.
It is yet another object of the present invention to provide a method and apparatus for unique identification of objects within a data processing system which forms a portion of a database of objects distributed among a plurality of data processing systems and/or data processing system networks without requiring the host data processing system to be connected to any other data processing system at the time the object identifier is assigned.
The foregoing objects are achieved as is now described. Each network of data processing systems within a system of networks is assigned a unique network identifier when connected to the system. Each data processing system within a given network is assigned a unique host system identifier when the data processing system is added to the network. When a new object is added to a given data processing system, a unique object identifier is constructed with three fields, including a high order field containing the network identifier for the network in which the object is being added, a next order field containing a host system identifier for the data processing system to which the object is being added, and an object identifier unique for all objects within the host data processing system. The combination of the three identifiers results in a single, unique object identifier which is unique for all objects across the system of networks and data processing systems. The host data processing system need not be connected to any other data processing system or network at the time the object is added to guarantee that the object identifier is unique across the entire system of networks. Therefore, the object may be added to a database of objects distributed among a plurality of data processing systems and accessed by an application communicating, when bandwidth is available, with other data processing systems over the Internet.
The above as well as additional objects, features, and advantages of the present invention will become apparent in the following detailed written description.